first off all you have no need for DDO (yuck) with any motherboard after 2002.
I would zero fill the drive (wipe and erase all data) then do a fresh install of windows.
You will lose all data on the drive; but with a DDO failure thats the end result anyway!
http://dban.sourceforge.net/
boot N nuke zero fill is
free but slow the process takes about 45 mintes per 20 gigs

but this will eliminate the DDO, dont put it back on when reinstalling windows, if your windows CD doesnt have Service Pack one or higher then simply slipstream your disk!
here is the how to for slipstreaming as I am "assuming" your need for DDO was the fact the OS couldnt see the 250 gig drive ??????????
http://www.techsupportforum.com/hard...ng-win-cd.html